Gearbox Failure

[bob turner]

Cautionary tale - when you let a model sit for four years, take it apart and lubricate it before serious operation.

My Boxpok Pacific (it will become Katy as soon as I get Callie to make the tender stick-ons, since Katy is the only railroad that operated Boxpok drivers on a small Pacific) ate its NWSL Mod O.5 gearbox last night. One of the worm bearings froze up, then ate its way aft out through the gearbox.

These things really did work, but one had to break them in with jeweler's rouge, and then hit them with a drop of oil once a year. I neglected to do that. I know better . . .

My "tender drive" switchers and narrow firebox SP locomotives all have a brass pillow block at the aft end of the frame, with an oil hole on top. If I don't stick a drop of oil in there now and then, they freeze up. Likewise Lobaugh driving boxes - they are square blocks of brass, and if left unlubricated for long, you need an arbor press to free them up.

so this is an excuse for a photo essay on repairing the NWSL gearboxes. I will dedicate it to Raoul, because without him over half my locomotives would be forever inoperative. I only wish I had bought a couple dozen 653-6 gearboxes when they were available with glass-filled gearbox castings.

Here is the Katy - a true workhorse of a model. I will get photos of the damaged gearbox and show you how I will repair it. Soon.

[bob turner]

I promise another better photo of that.

I found a new O.5 case, and thought I had installed it. In the confusion I found I had grabbed the old case halves. Model made it about forty feet under load, then failed in the identical fashion. That is when I discovered my mistake. Test run this evening with the new case halves.

To repair the older halves, I plan to add JB Weld. I need to coat the worm shaft bearings with some release agent, and am open to suggestions. Candle wax seems like it would be too thick. I will do them one half at a time. The JB Weld will not adhere to the Celcon, so I am drilling holes in the remaining parts of the halves to enable a mechanical bond.

I should add that, before Raoul came out with the Mod O.6, I figured out how to convert the O.5 shaft to ball bearings. I may get into that as well, although I am sure I covered it in an old OSN.

I do like Maroon's latest four axle Diesel. Too bad the Penn Erie patterns are not still with us! But I guess I have my share . . .

[bob turner]

JB Weld worked. I cleaned the damaged area out, drilled a #50 hole in each half so the JB would have a physical anchor, coated the bearing and rear thread of the worm with candle wax, and heated it so only a thin layer was left, put the JB in, put the worm and bearing assembly in, and screwed the halves together. This morning I pried the halves apart, and presto - I have a good gearbox.

I have not put it in to service, but suspect it will work just fine.